Medial arch strain after medial displacement calcaneal osteotomy: An in vitro study

Posterior tibial tencfon dysfunction with concomitant progressive flatfoot deformity is associated with ligamentous failure along the medial arch. Med ial displacement calcaneal osteotomy is being used alone and in combination with other procedures, with the expectation that it contributes to maintai ning the arch. The objective of this study was to examine the effect of ost eotomy on reducing medial arch strain. Whole cadaver feet were subjected to vertical loads while plantigrade. Spring ligament length was monitored usi ng liquid metal displacement gauges. Two outcomes were examined: the length of the ligament under one-half body weight and the change in length of the ligament per unit of applied load. The medial displacement calcaneal osteo tomy allowed elongation of the ligament with weightbearing, but at a shorte r ligament length. This afforded the spring ligament protection from the le vels of force experienced in the intact and lateral column-lengthened condi tions.